SECTION 252:626-19-2. Installation of piping

(a)   Standards. The standards in this Section apply to the installation of piping in public water supply distribution systems. Specifications must incorporate the provisions of the AWWA standards.

(b)   Bedding. Provide continuous and uniform bedding in the trench for all buried pipe. Tamp backfill material in layers around the pipe and to a sufficient height above the pipe to adequately support and protect the pipe. Remove all stones found in the trench to a depth of at least 6 inches below the bottom of the pipe.

(c)   Cover. Provide all water mains with at least 30 inches of cover or with sufficient insulation to prevent freezing.

(d)   Blocking. Provide reaction blocking, tie rods, or joints designed to prevent movement at all tees, bends, plugs and hydrants to prevent movement of the pipe.

(e)   Pressure and leakage testing. Test the installed pipe for leakage in accordance with AWWA standard specifications. Leakage must not exceed 10 gal/inch diameter per mile of pipe per 24 hours at 150 psi testing pressure.

(f)   Disinfection and testing. Disinfect all waterlines according to AWWA standard specifications. Obtain safe bacteriological samples on two consecutive days before placing the waterline into service.

(g)   Permeation of system by organic compounds. Where distribution lines are installed in areas of soil or groundwater contamination by organic compounds use:

(1)   pipe and joint materials that are not subject to permeation by organic compounds.

(2)   non-permeable materials for all portions of the system including water mains, service connections, and hydrant leads.

(h)   Separation of water mains and sewers from contamination sources.

(1)   Horizontal separation.

(A)   Measure the separation distance edge to edge.

(B)   Locate water mains at least 10 feet horizontally from any existing or proposed sewer lines.

(C)   Locate water mains at least 5 feet horizontally from any existing or proposed storm sewers, raw water lines, petroleum product lines, natural gas lines, and other buried utility lines.

(D)   Locate cast iron waterlines at least 10 feet from any gasoline storage tank and lines and PVC water lines at least 50 feet horizontally from any gasoline storage tank and lines.

(E)   Locate waterlines at least 15 feet from all parts of septic tanks and absorption fields, or other sewage treatment and disposal systems.

(2)   Vertical Separation.

(A)   Measure the separation distance from edge to edge.

(B)   Lay waterlines crossing sewer lines to provide a minimum vertical distance of 24 inches between the water main and the sewer line. Arrange the piping so that joints in a 20-foot length of PVC or 18-foot length of cast iron sewer pipe will be equidistant from the water main. Where a water main crosses under a sewer, provide adequate structural support for the sewer to prevent damage to the water main.

(C)   Maintain a 2-foot vertical separation between waterlines and any existing or proposed storm sewers, raw water lines, petroleum product lines, natural gas lines, and other buried utility lines.

(3)   Special conditions. When it is impossible to obtain proper horizontal and vertical separation as stipulated in (1) and (2) of this subsection, design and construct the other line equal to water pipe, and pressure test it to assure water tightness of joints adjacent to the water line prior to backfilling.

(i)   Surface water crossings.

(1)   Above-water crossings. Adequately support and anchor the pipe. Provide protection from damage and freezing. Make waterline accessible for repair or replacement.

(2)   Underwater crossings. Provide a minimum cover of 2 feet over the pipe. For waterlines crossing a well defined channel bottom greater than 15 feet in width, construct the waterline as follows:

(A)   design the pipe for river crossings and have flexible, restrained or welded watertight joints,

(B)   provide valves at both ends of water crossings so that the section can be isolated for testing or repair. The valves must be easily accessible and not subject to flooding. The valve closest to the supply source must be in a manhole, and

(C)   make permanent taps on each side of the valve within the manhole to allow insertion of a small meter for testing to determine leakage and for sampling purposes.

(j)   Tracer wire. Install metal tracer wire on all non-ferrous piping used for public water supply mains.

[Source: Added at 18 Ok Reg 1612, eff 6-1-01; Amended at 25 Ok Reg 2304, eff 7-11-08; Amended at 31 Ok Reg 1301, eff 9-12-14; Amended at 33 Ok Reg 1472, eff 9-15-16]